Reversing motion for loom let-offs



w. H. WAKEFIELD REVERSING MOTION FOR LOOM LET-OFFS Filed July 27, 1925 21 if 45 10 141344 439 4/ I 33 I 1' V :LLL-H w w: U I l mm 1 g 5 30 v z; 16 v Z4 19 L is? I I T I firm/or I; J i W 11 Alfanys Patented Mar. 8, 1927.

U NITED STATES PAT E NT OF FIC WALTER H. WAKEFIELD, 0F. WORCESTER", MASSACHUSETTS, ASSIGNOR'TO CROMIBTON- & KNOWLES LQOM WORKS, 013 "WORCESTER, MASSACHUSETTS, A CORPORATION'OF' MASSACHUSETTS.

REVERSING. MOTION FOR LOOM LET-GEES.-

Applieation filed July. 27, 1925.

This invention relates to left-0ft motions for looms and more particularly to means for reversing the warp at the time of a pickout so that the clothv may be let back the proper distance before weaving is resumed.

In the weaving of fabrics such as duck a defective pick of filling is occasionally woven into the fabric and it is necessary for the weaver to pick out or reverse the picking operations to remove allpicks which were laid after the imperfection occurred. lVhen this step is completed the fell of the cloth must be moved back to the reed line and it is desirable that the warp threads be under the same tension as that which prevailed before the pick out.

It is accordingly the principal object of my invention to employ the usual'and well known adjusting mechanismfor the friction of the left-oft" in such a way that saidmechanism may be released from its normal position and used to reverse the warp, whether the latter be delivered by a beam or the drum usually employed in connection with a creel.

A more detailed object of my invention is to mount the usual friction band on members which are normally stationary but which may be moved at will in one direction to slacken the band so that the same may takea fresh hold on the friction drum and then be moved in the other direction to tighten the band on the drum andcause a partial rotation of the latter.

\Vith these and other objects in view which will appear as the description proceeds, my invention resides in the combination and arrangement of parts hereinafter described and set forth in the claims.

In the accompanying drawings where I have shown my invention as applied to a duck loom having a delivery drum such as is used in conjunction with a creel.

Fig. 1 is a vertical sectionv through the loom intermediate the loom sides and showing the device in normal operating position,

.Fig. 2 is a. view similar to Fig. 1 but showing the position the parts assume when a rewinding motion is to be given the drum,

Fig. 3 is a section 011 line 33of Fig. 1,

Fig. 4 is an enlarged side elevation of the pawl. which aids in preventing retrograde movement of the drum and- Serial No. 46,282.

Fig. 5 is a detail vertical section through the locking ing position.

Referring more particularly to the draw ings it will be seen that I. have provided a loom frame 10 having a warp delivery drum 11 the end of which has secured thereto a gear 12 meshing with a pinion 13. Said pinion 13 is secured to a cross shaft' 14 on which is fixed in any approved manner a drum 15. A flexible friction band 16 surrounds a portion. of the drum 15 and has one end thereof anchored to a normally fixed stud 17 and the other. end secured to a stud" 18 carried by a lever 19.

At the front of the loom there is provided the usualvertieal screw 20 movable between bearings 21. secured to the loom side androtat'able-by means of a hand wheel 22. A block 23 is loosely mounted on the screw 20 and is moved up and down as the latter is rotated. Said block is provided with a pin showing the same in lOCkT- notch 24 which supports the forward endof the lever 19 so that as'the screw is turned theband 16 will be tightened or loosened to increase or diminish the friction on the drum 15. The matter thus far describedis of common construction and introduces no departure over devices well known in the art.

My. improvements relate to means for moving the friction band as a whole about the axis of the drum 15 to the endthat the strap may be slaekened when handle 19 is moved down and may be tightened when said handle is raised. In carrying out my improvements I provide an arm 30 which is pivoted on the shaft 14 and carries the normally fixed stud 17. The handle 19 is pivoted'to said arm as at 81 and said arm is provided with anopening 32 normally occupied by a pin 33 shown in det'ail'in Fig. 5. A lever 34 is pivoted as at 35. to the loom frame and has a cam face positioned" for engagement with the'head87 of the'pin 33. A spring 38 acts normally to move the pin out of the opening 32'but is held from doing so by the broad part of the lever 84" which engages the head 37'to holdlsaid pin in the opening 82.

The rear end of lever 34 has pivoted thereto a pawl. 39 which is' normally supported by alug 40 formed'on' the lever 34 and so long as the latter is in normal position the pawl will be held above the ratchet wheel all rigid with the drum 15. Foot lever 42 moves about a fixed pivot s3 and is connected by an adjustable upright rod 452 to lever so that as the foot lever is depressed the pawl will be lowered into operative relationship with respect to the ratchet and the cam face ti'formed on lever 34: will be raised to permit spring 38 to withdraw the pin 33 from the opening 82.

Under normal conditions the pin 33 is in the opening 32 so that both studs 17 and 18 are in fixed position and any adjustments of lever 19 will be con'imunicated directly to the friction band 16. At the time of picking out lever 19 will be flexed off block 24, after which foot lever 42 will be depressed to permit the withdrawal of pin 33 from opening 32. This unlocks arm 30 and permits the same to move freely about shaft 14. Lever 19 will now be moved downwardly by the operator, this action being accompanied by a downward movement of the arm 30 and a slackening of the band 16. The pawl 39 will also fall into operative position with respect to ratchet ll. Should the band stick and tend to hold the arm 30 raised, a finger 45 on lever 19 will engage a boss 48 on said arm and positively lower said arm. When the lev r 19 has been lowered sufficiently the operator will raise the same, which will result in atightening of the band 16 about the friction drum and cause a reverse motion of the warp delivery drum. This operation may be repeated as often as necessary to restore the fell of the cloth to the reed line, after which the lever 19 may be sprung over the notch let, the pin 33 having previously been inserted in the opening 32 by the release of foot lever 42. The parts are thus restored to their normal position and the friction is the same after the pickout as it was before.

From the foregoing it will be seen that l have provided a simple device for reversing the warp of the loom by the simple manipulation of the hand lev r usually employed in the type of loom to which the invention relates and that the friction is the same after the pick-out as it was before.

Having thus described my invention it will be apparent that changes and n1odilicalions may be made therein by those skilled in the art without departing from the spirit and scope of the invention, and I do not wish to be limited to the details herein disclosed but what I claim is:

1. In alet-off mechanism for a loom having a warp delivery means and a friction surface operatively connected therewith, a friction band cooperating with the friction surface to retard movement of the warp delivery means, normally stationary means to support said band and hold the same in close contact with the friction surface, and means to move said band as a whole in one direction about the axis of the friction surface to an abnormal position to slacken said band and in the opposite direction to tighten said band while in the abnormal position and to thereafter restore said band to nor mal position.

2. In a let-off mechanism for a loom having a warp delivery means and a friction surface operatively connected therewith, an arm movable about the axis of the friction surface but normally locked in stationary position, a hand lever pivoted to said arm, means to adjust said lever with respect to the arm, a friction band having one end secured to the arm and the other end to said lever to cooperate with the friction surface'and retard movement of the warp dclivery means, said arm and hand lever being releasable from locked position to move in one direction to slacken the band and in the opposite direction to tighten the band around the friction surface.

3. In a let-off mechanism for a loom having a warp delivery means and a friction surface operatively connected therewith, an arm normally stationary but movable about the axis of the friction surface, a manually controllable lever pivoted to the arm, means for adjusting the position of the lever with respect to the arm, and a friction band in operative contact with the friction surface and having one end thereof secured to the arm and the other end secured to the lever, the arm and lever being movable from normal stationary position to move as a unit about the axis of the friction surface in one direction to slacken the friction band and movable as a unit in the opposite direction to tighten the band about the friction surface.

In a let-off mechanism for a loom having a. warp delivery means and a friction surface operatively connected therewith, a pair of members pivotally connected to gether, one of said members l'aeingg; normally stationary but movable about the axis of the friction surface, and the other member adjustable with respect to the first named member, a flexible friction band cooperating with the friction surface to retard movoment of the warp delivery means, said band having one end secured to one of the members and the other end secured to the othe member, said members being movable from normal position to move as a unit about the axis of the friction surface in one direction to slacken the friction band and movable as a unit in the other direction totighton said band.

5. The method of causing reverse movement of loom warp delivery means having a rotary member movable with thedelivery means and a friction band normally tightly drawn around a portion of the rotary member, consisting in loosening the friction band with respect to the rotary member, moving the band as a whole angularly with respect to the rotary member to an abnormal position, tightening the band with respect to the rotary member in the abnormal position, and returning the band so tightened to normal position to cause movement of the retary member.

6. In a let-off mechanism for a loom having a warp delivery member and a friction surface operatively connected thereto and movable therewith, a friction band normally in contact with the friction surface to resist advance movement of the warp delivery member, means to slacken the friction band and move the same as a whole to an abnormal position with respect to the friction surface, mechanism to prevent advance movement of the warp delivery member when the friction band is slackened with respect to the friction surface, said first named means effective to tighten the band around the fric tion surface and to thereafter restore the band from abnormal to normal position and simultaneously effect a reverse movement of the warp delivery member.

7. In a let-off mechanism for a loom having a warp delivery member and a friction surface operatively connected thereto and movable therewith, a normally stationary flexible friction element engaging the friction surface to resist advance movement of the warp delivery member, a device to support said element in normal position, mechanism to simultaneously release said element supporting device and to prevent advance movement of the warp delivery member, said device when released slackening the element relatively to the friction surface and moving the same to abnormal position, said support thereafter being movable to tighten the element with respect to the friction surface and then movable to return the element from abnormal to normal position to effect a. reverse movement of the warp delivery member.

8. In a reversing mechanism for a loom warp delivery member having a friction surface operatively connected thereto and movable therewith, a flexible friction element for the friction surface, an arm to support one end of the element, a lever pivoted on the arm and attached to the other end of the element, a holding device for the arm to hold the latter normally in fixed position, and

arm being movable to slacken the flexible I element and moving the latter to an abnormal position, and said arm and lever thereafter being movable to tighten the element on the friction surface and being then movable to return said element from abnormal to normal position to effect a reverse movement of the warp delivery member.

9. In a reversing mechanism for a loom warp delivery member having a friction surface operatively connected thereto and movable therewith, a flexible friction element for the friction surface normally serving to resist advance movement of the warp delivery member, and means to slacken the element with respect to the friction surface and to thereafter move said element as a whole in a direction corresponding to an advance movement of the warp delivery member to an abnormal position, said means thereafter being movable to tighten the friction element while in abnormal position and then movable to restore said element to normal position and effect a reversal of the warp delivery member.

10. In a reversing mechanism for a loo-m Warp delivery member having a. friction surface operatively connected thereto and movable therewith, a flexible friction element for the friction surface to resist advance movement of the warp delivery member, normally stationary but movable supporting means for the friction element, said supporting means being movable to slacken the friction element and thereafter moving said element in a direction corresponding to an advance movement of the warp delivery member to an abnormal position, and mechanism to prevent advance movement of the warp delivery member when the element is moving in a direction corresponding to an advance movement of the warp delivery member, said supporting means thereafter being movable first to tighten the element with respect to the surface and then to move said element from abnormal to normal position in a direction corresponding to a reverse movement of the warp delivery member.

In testimony whereof I have hereunto affixed my signature.

WALTER H. WAKEFIELD. 

